On non-isotropic harmonic maps of surfaces into complex projective spaces

It is proved by purely algebraic method that weakly conformal, conformal and Az3 = 0 are mutually equivalent if φ: Ω→CPn is a non-isotropic harmonic map and the harmonic maps with isotropy order ≥3 are uniquely determined by a system of ordinary differential equations. A method is given, by which the isotropy orders of non-isotropic harmonic maps can be computed.